Testing system



H. M. PRUDEN TESTING SYSTEM Nov. 10 1925; v 1,560,727

Filed. Jan. 23. 1923 Wye/7m n Ham/d Prude/z xi/La Patented Nov. 10, 1925.

UNITED STATES "1,560,727 PATENT OFFICE.

mmow 1r. raumm, or mromen, new messy, ASSIGNOB 'ro 'wamm rare comm,- mcomoiwmn, or new YORK, n. "1., A conronurron'or new you.

5T TESTING SYSTEM.

Application filed January as, 192:. Serial in. 014,375.

To all whom it may concern: Be it known that I, .HARonn M. PRUDEN,

a citizen, of the United States,residing at East Orange, in the "county of Essex and State of New Jersey, have invented certain new and useful Im rovements in Testing Systems, of which t e following is a full, clear, concise, and exact description.

' This invention relates to electrical testing systems and more particularly to systems for testing the adjustment of polarized relays, interrupters and the like.

The object of the resent invention is to test the contact ad1ustment of a circuit changing devioesuch as apolarized relay, while it is in operation.

This is accomplished by translating the pressure between the contacts into a suitable effect, for example, into a varying lamp luminosity indicative of the degree of contact pressure.

The invention will be readily understood from the following detailed description and by reference to the accompanying drawing which shows the testing circuit and visual indicating means employed in detecting-the difference in contact pressure exerted by the armature of a vibratin relay on its associated contact and the diiference in duration of engagement of the armature with its contacts.

In the drawing a circuit changing device 1, such as a relay arranged for quick connection with and dlsconnection from the circuit with which it is to be used by means of plugs which are adapted to engage with spring jacks, is shown connected with the testing circuit.

The relay 1 is provided with an'armature 4 which is caused to vibrate between the stationary contact points 5 and 5 by means of the operating coils 6. In this connection it is assumed that any well known polarizing means are rovided to enable the armature to operate reely upon periodic reversals occurring in the operating currentsource connected to the terminals 7 and 8. A key 9 is provided for closing the circuit for the operating current through the operating coils6 and also for placing ground upon the armature 4, the purpose of which will be hereinafter explained. I

The actuation of key 9 establishes a circuit which may be traced from the current source, (not shown), the lower alternate contact of key 9, the windings of the milliammeter 13, conductor 20, contacts of the plug 2, windings of relay 6, contacts of plug conductor 21, resistance element 15, the upper portion of the potentiometer 12 and back thereupon energizes whereupon its armature 4 alternately engages the contacts 5 and 5. \Vhen the armature 4 rests on the contact 5 a circuit exists which may be traced from grounded battery 11, filament of lamp '10, contacts of plug 22, contact 5, armature 4, contacts of plug23, to ground over the upper alternate contact of key 9. The lamp 10 will be illuminated in this circuit.

When the armature 4 rests on the contact '60 to the original current source. Relay 6 5, a circuit may be traced from grounded I battery 11, filament of lamp 10, contacts of plug 24, contact 5, armature 4, contacts ofplug 23 to ground over the upper alternate contact of key 9. The lamp 1O illuminates in this circuit.

Since the duration of engagement of the armature 4 with the contacts 5 and 5" depends on the pressure exerted thereon by the armature, it follows that, with a device such as described in which the two circuits are firapidly made and broken, if the contact 5 is so adjusted relative to 5 that in operating, the armature exerts a greater pressure on contact 5, that is, remains in engagement- With it longer than with 5, the lamp 10 will glow with a greater brilliancy than lamp 10, and conversely. By adjusting the con tacts 5 and 5* imtil the lamps 10 and 10 glow with equal brilliancy, a condition is reached where the armature 4 exerts an equal pressure on the contacts 5 and 5.

The potentiometer 12, resistances 14 and 15 and the milliammeter 13 are provided so that the operating current may be regulated in such a manner as to test relay 6 under general working conditions.

What is claimed is:

1. In a testing system, in combination with a relay to be tested having an armature adapted to vibrate between two stationary contacts in response to alternating current, a source of alternating current for causing the operation of said armature, a second source of current, a circuit including said armature, said second current source, an indicating lamp and one of said stationary contacts, and another circuit including the same said armature and second current source, another indicating lamp and said other stationary contact.

.2. In a testing system, in combination with a polarized alternating current relay to be tested having a reed armature adapted when energized to vibrate between and make contact with two stationary contacts, an indicating lamp for each of said contacts and a source of testin current therefor so connected that one 0 said stationary contacts, one of said lamps, said current source and said armature are included in one circuit, and the other stationary contact and lamp, and said same current source and armature are included in a second circuit whereby when said armature is vibrated both of said indicating lamps will burn with substantially equal brilliancy when said stationary contacts are properly adjusted with respect 0 to said armature.

3; A contact testing arrangement for pclarlzed alternating current relays of the vibratlng reed armature type having two stationary contacts between which said armature is adapted to vibrate and make contact when said relay is energized which comprises a source of testing current, an indicatmg lamp for-each contact, and switching means for connecting in one circuit said current soume, one of said lamps, said armature and one of said contacts, and in another circuit said current source the other lamp, said armature and the other contact, sald switching means being also adapted for connecting the operating winding of said relay to a source of operating current.

In witness whereof, I hereunto subscribe my name this 19th day of January A. D.,

HAROLD M. PRUDEN. 

